Re: Method R and CPU Time

Recently I was involved in analyzing the performance of a big Oracle
8.1.7.4 and got Statspack
reports from an all day long with snaps at every half hour. To use meth=
od
R, I picked the following
data from the Statspack reports:

1 - Total CPU time from the line: CPU used when call started
2 - Total Wait Time from the sum of the wait time column of the top 5 w=
ait
events

Then I noticed that the CPU time sometimes were in excess of the elapse=
d
time (30 min).
As the system is a Sun SF10K running with 44 CPU I calculated the avera=
ge
CPU rate
scaled to the number of CPUs. That is CPUavg=3D (CPU time/elapsed time)=
/ 44.
The numbers I found for each interval were in turn very reasonable and=

pretty followed the
transactions per second rate.

Anyway on some periods I found the relation between the original Total =
CPU
time and the Total
wait time very odd with values like 0.02 % of total time(CPU/(CPU+WAIT)=
.

I used also the Anjo Kolk oraperf analyzer but there the wait times are=

being multiplied by 100
on the response time calculation giving very small figures for the CPU =
rate
results.

Does anyone have seem this behavior when analyzing Oracle running on
massive multiprocessor systems ?

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